Bloodhound, welcome to the forum.
For Montana, I'm thinking you'd want a rod with some guts to cast a wide range of fly sizes including some hoppers and stoneflies, as well as other smaller dries, weighted nymphs, indicator/dropper rigs, and occasional streamers, as well as deal with windy conditions on big water. So unless you're fishing primarily small flies on spring creeks, I'd think the 5 weight would be more of a go to rod than a 3 or 4 weight.
So you may want to rethink the Sage Launch as a 5, and go with a less expensive rod for the smaller version. I haven't used one, but the Cabelas Three Forks 7'6" 3 weight is supposed to be a pretty sweet stick for not a lot of money (around 50 bucks) if you're looking for a short rod for small brushy streams fishing mostly small dries...
As for a 5 weight, you have a lot of choices and the best advice would be to try a bunch to see which ones sing sweet songs to you. In addition to the more expensive Launch, TFO and Redington make some good inexpensive rods. But I'd also give the Albright A5 9' 5 weight a good hard look. It's a great rod at a great price: A-5 Fly Rods - English
Good luck, I'm sure others will weigh in with some good recommendations too.